For an Org file myfile.org, the ODT file will be
myfile.odt. The file will be overwritten without warning. If there
is an active region,151 only the region will be exported. If the selected region is a
single tree,152 the
tree head will become the document title. If the tree head entry has, or
inherits, an EXPORT_FILE_NAME property, that name will be used for the
export.

C-c C-e o O
Export as an OpenDocument Text file and open the resulting file.